Integrated switched capacitor bank

ABSTRACT

A switched capacitor bank assembly including a first capacitor, a first switch selectively connected between the first capacitor and a first phase line, and a first voltage sensor integrated within a housing of the first switch and configured to sense a voltage of the first phase line. The assembly further includes a controller including an electronic processor, the controller operably coupled to the first voltage sensor and the first switch. The first capacitor, the first switch, the first voltage sensor, and the controller are physically supported by a frame of the switched capacitor bank assembly.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Pat. ApplicationNo. 63/238,494, filed Aug. 30, 2021, the entire content of which ishereby incorporated by reference.

FIELD

Embodiments relate to capacitor bank switch assemblies.

SUMMARY

Switched capacitor banks may be installed on poles and/or at substationsto apply power factor correction (e.g., by altering the load phasing) tothe power grid in response to the application and removal of heavyindustrial inductive loads. When loads are not in phase, additionalreactive currents increase transmission losses, which may result inwasted energy and a need for additional generating capacity. Thus,capacitor banks are used to help improve the transfer efficiency ofelectrical energy being transmitted through the power grid. Charging anddischarging of the capacitors is controlled with switches based on powerfactor correction needs of the grid.

FIG. 1 illustrates an exemplary capacitor bank assembly 100 according toexisting switched capacitor banks of the prior art. Existing switchedcapacitor banks, such as the assembly 100, are highly complex,engineered-to-order solutions that require a combination of severalcomponents provided by various manufacturers. Key components of atypical switched capacitor bank include capacitors, capacitor switches,a controller, current and/or voltage sensors, junction boxes, cableassemblies, arrester, wildlife protectors, power transformers, and otherdevices.

For example, the illustrated switched capacitor bank assembly 100, whichis a pole-mounted assembly used in medium voltage applications (e.g.,approximately 5 kV -38 kV), includes numerous third-party componentsthat are separately installed and interconnected by an assembly ofcables. As shown, the assembly 100 includes a capacitor bank 105 that isinstalled on distribution pole 107 at an elevation between approximately30 and 50 feet above ground. The capacitor bank 105 includes capacitors110, capacitor switches 115, a junction box 120, and a power transformer125. The assembly 100 further includes voltage sensors 130, which areinstalled at the top of distribution pole 107 (e.g., approximately 40-50feet above ground), and a control cabinet, or controller, 135, which isinstalled at the bottom of distribution pole 107 (e.g., approximately 5feet above ground). The assembly 100 further includes numerous cables140 that are needed to interconnect the components of the assembly 100.For example, one or more sensor cables 140A, which may be 14-pin cablesthat exceed 40-50 feet in length, are used to connect the voltagesensors 130 to the controller 135. In addition, one or more controlcables 140B, such as 19-pin cables, are needed to connect the controller135 to the capacitor switches 115, the junction box 120, and/or otherworking components of the assembly 100.

Given the complexity and variety of third-party components included inexisting switched capacitor bank assemblies, system integrators arefrequently relied upon during the installation process. As a result,these assemblies may require long install times, may be difficult totroubleshoot, and may be expensive to maintain over the course of a 20+year product lifespan. In addition, the sensing accuracy in existingcapacitor bank assemblies may suffer due to magnitude and phase errorsand signal interference caused by lengthy sensor and control cablesincluded in the assembly. Thus, a solution that simplifies thecomplexity of the capacitor bank assembly, reduces installation time,and significantly reduces the troubleshooting and maintenance costsassociated to capacitor banks over the life of the capacitor bank isdesired.

One aspect of the present disclosure provides a switched capacitor bankassembly including a first capacitor, a first switch selectivelyconnected between the first capacitor and a first phase line, and afirst voltage sensor integrated within a housing of the first switch andconfigured to sense a voltage of the first phase line. The switchedcapacitor bank assembly further includes a controller that includes anelectronic processor and is operably coupled to the first voltage sensorand the first switch. The switched capacitor bank assembly furtherincludes a frame arranged to physically support the first capacitor, thefirst switch, the voltage sensor, and the controller.

Another aspect of the present disclosure provides a multi-phase powersystem a plurality of phase lines, which includes a first phase line, asecond phase line, and a third phase line, and a switched capacitor bankassembly. The switched capacitor bank assembly includes a plurality ofcapacitors including a first capacitor, a second capacitor, and a thirdcapacitor, a plurality of voltage sensors including a first voltagesensor for measuring a voltage of the first phase line, a second voltagesensor for measuring a voltage of the second phase line, and a thirdvoltage sensor for measuring a voltage of the third phase line, and aplurality of switches including a first switch connected between thefirst phase line and the first capacitor, a second switch connectedbetween the second phase line and the second capacitor, and a thirdswitch connected between the third phase line and the third capacitor.The switched capacitor bank assembly further includes a controllerincluding an electronic processor and coupled to the plurality ofvoltage sensors and the plurality of switches, the controller configuredto selectively connect, using the plurality of switches, the pluralityof capacitors to the respective ones of the plurality of phase linesbased on signals received from the plurality of voltage sensors.Furthermore, the switched capacitor bank assembly includes a framearranged to physically support the plurality of capacitors, theplurality of voltage sensors, the plurality of switches, and thecontroller.

Other aspects of the disclosure will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a switched capacitor bank assembly according to theprior art.

FIG. 2A illustrates a switched capacitor bank assembly according to someembodiments.

FIG. 2B illustrates a switched capacitor bank assembly according to someembodiments.

FIG. 3A illustrates a first perspective view of the switched capacitorbank assembly of FIG. 2A or FIG. 2B.

FIG. 3B illustrates a second perspective view of the switched capacitorbank assembly of FIG. 2A or FIG. 2B.

FIG. 4 illustrates a schematic diagram of a distribution networkaccording to some embodiments.

FIG. 5 illustrates a block diagram of a control system of the switchedcapacitor bank assembly of FIG. 2A or FIG. 2B.

FIG. 6A illustrates a switched capacitor bank assembly according to someembodiments.

FIG. 6B illustrates a switched capacitor bank assembly according to someembodiments.

FIGS. 7A-7K illustrate a switched capacitor bank assembly according tosome embodiments.

DETAILED DESCRIPTION

FIG. 2A illustrates an integrated switched capacitor bank assembly, or“integrated assembly,” 200 according to some embodiments of the presentdisclosure. FIGS. 3A-3B illustrate close-up perspective views of theintegrated assembly 200. When compared to the prior art assembly 100 ofFIG. 1 , all of the components of the integrated assembly 200 arecontained within a single package. As will be described in more detailbelow, the integrated assembly 200 includes a frame 205 that is arrangedto physically support the components, such as, but not limited to,capacitors 210A-210C, capacitor switches 215A-215C, dielectric bushings220A-220C, voltage sensors 225A-225C, a controller 230, a communicationmodule 235, and/or a power transformer 240, included in the integratedassembly 200. Accordingly, installation of the integrated assembly 200is simplified and less expensive when compared to the prior art assembly100 of FIG. 1 . That is, the integrated assembly 200 does not includevarious third-party components that are separately installed at varyingheights along a distribution pole and interconnected by long andexpensive cable assemblies. Rather, as shown in FIG. 2A, the integratedassembly 200 can be installed at a single location, such as 40 feetabove ground, on a distribution pole 245 without the need for lengthycables to interconnect components. In addition, none of the componentssupported on the frame 205, such as the controller 230, are easilywithin reach of would be thieves or other malicious actors.

FIG. 2B illustrates an embodiment in which the integrated assembly 200is additionally connected to, via one or more sensor cables, one or morecurrent sensors 250A-250C positioned atop the distribution pole 245.However, it should be understood that the integrated assembly 200 iscapable of operating without being connected to the one or more currentsensors 250A-250C. In addition, although described as being mounted on adistribution pole 245, it should be understood that the integratedassembly 200 may also be pad mounted. For example, the integratedassembly 200 may be installed as a pad mounted assembly at a substation.

As shown in FIGS. 3A-3B, the frame 205 of the integrated assembly 200includes a combination of brackets, beams, and other structuralcomponents arranged to physically support the integrated assembly 200and one or more additional arresters. For example, the frame includesarrester mounts 206 to which one or more arresters can be coupled. Theframe 205 is further arranged to be physically coupled to thedistribution pole 245 by one or more mechanical fasteners such as bolts,screws, and/or rivets. The frame 205 is constructed from various metals,plastics, wood, and/or any suitable combination thereof.

In addition, the frame 205 includes one or more housings that arearranged to physically support and protect components of the integratedassembly 200. For example, the frame 205 includes an enclosure, or tank,300 that houses the control electronics, including controller 230, ofthe integrated assembly 200. The tank 300 is configured to shield thecontrol electronics from environmental damage and/or any electromagneticinterference that would otherwise be caused by the higher voltagecomponents of integrated assembly 200. In some embodiments, the tank 300includes a sealed compartment with a door to access the controller 230and other electronics housed within. In some embodiments, the tank 300additionally houses the communication module 235 and an internal powersource. In some embodiments, the frame 205 supports one or moreadditional enclosures and/or compartments that are arranged toseparately house the communication module 235 and internal power source.

FIG. 4 illustrates a schematic diagram of an example multi-phase powersystem, such as a distribution network, 400 in which the integratedassembly 200 is installed. As shown, the distribution network 400includes a power source 405, a transformer 410, and three-phasedistribution, or phase, lines 415A-415C. The transformer 410 isconfigured to step down the voltage supplied by power source 405 to alevel (e.g., approximately 5 kV - 38 kV) to be distributed by the phaselines 415A-415C. Although described as being a medium voltagedistribution network, it should be understood that network 400 myimplemented as a high voltage transmission network, a secondary lowvoltage (e.g., approximately 120 V - 240 V) distribution network, and/orany other power distribution network that is desired. Similarly,although the power source 405 included in network 400 is a three-phasealternating current (AC) power source, it should be understood thatother types of power sources may be used instead.

When the integrated assembly 200 is installed in the distributionnetwork 400, each of the capacitors 210A-210C may be selectivelyconnected to the phase lines 415A-415C by capacitor switches 215A-215C.In particular, the first capacitor 210A is selectively connected betweenthe first phase line 415A and ground 420 by the first capacitor switch215A. Similarly, the second capacitor 210B is selectively connectedbetween the second phase line 415B and ground 420 by the secondcapacitor switch 215B. Likewise, the third capacitor 210C is selectivelyconnected between the third phase line 415C and ground 420 by the thirdcapacitor switch 215C.

In some embodiments, each of the capacitors 210A-210C are implemented asa capacitor bank. In such embodiments, the capacitor banks include aplurality of capacitors electrically connected in series and/or parallelwith one another. In some embodiments, the capacitors 210A-210C areimplemented as single capacitors.

In some embodiments, the capacitor switches 215A-215C are implemented asvacuum interrupters. In the example illustrated, the first capacitorswitch 215A is implemented as a vacuum interrupter that includes aswitching rod and is powered by a solenoid or magnetic actuatormechanism. In such an example, the solenoid and/or magnetic actuatormechanism is controlled by signals received from controller 230 and/orthe operating handles 305A-305C supported by switch tank 300. As shownin FIGS. 3A and 3B, each respective capacitor switch 215A-215C mayinclude a solid dielectric housing that encapsulates a respective vacuuminterrupter. The solid dielectric switch housing may be formed of aninsulating epoxy and/or urethane material. The capacitor switches215A-215C further include solid dielectric bushings 220A-220C forrespectively connecting to phase lines 415A-415C. The solid dielectricbushings 220A-220C are positioned atop the capacitor switch housings andmay be formed of the same insulating material as the capacitor switchhousings. In some embodiments, the capacitor switches 215A-215C areimplemented as other types of switches, such as breakers or relays.

With reference back to FIG. 4 , the integrated assembly 200 furtherincludes voltage sensors 225A-225C that are respectively configured tosense the line voltages of phase lines 415A-415C. For example, the firstvoltage sensor 225A is electrically connected in parallel with the firstcapacitor 210A and first capacitor switch 215A and configured to sense avoltage of the first phase line 415A. Similarly, the second voltagesensor 225B is electrically connected in parallel with the secondcapacitor 210B and second capacitor switch 215B and configured to sensea voltage of the second phase line 415B. Likewise, the third voltagesensor 225C is electrically connected in parallel with the thirdcapacitor 210C and third capacitor switch 215C and configured to sense avoltage of the third phase line 415C.

When compared to the prior art assembly 100 of FIG. 1 , the voltagesensors 225A-225C included in the integrated assembly 200 are notmounted to the top of distribution pole 245. Rather, as shown in FIGS.3A and 3B, each one of the voltage sensors 225A-225C may be integratedwithin the solid dielectric material of the bushings 220A-220C and/orthe housings of the capacitor switches 215A-215C. For example, the firstvoltage sensor 225A may be embedded within the insulated epoxy resin ofthe first bushing 220A and/or the housing of the first capacitor switch215A. Thus, there is no need for a long sensor cable, such as the 40foot sensor cable of prior art assembly 100, to connect the firstvoltage sensor 225A to the controller 230. Rather, only a short cable orother small conducting medium may be needed to connect the embeddedvoltage sensor 225A to the controller 230, as the controller 230 ishoused within the switch tank 300 proximate the embedded voltage sensor225A. Similarly, only short cables or other small conducting mediums maybe needed to connect the second and third voltage sensors 225B, 225C tothe controller 230.

When compared to the voltage sensors 130 of the prior art assembly 100,which are connected to controller 135 by lengthy (e.g., approximately40-50 ft) sensor cables, the voltage sensors 225A-225C of the integratedassembly 200 operate with increased accuracy. In particular, voltagereadings provided by the voltage sensors 225A-225C to the controller 230are not subjected to the negative effects of phase shifting or magnitudeaccuracy issues that are often associated with lengthy sensor cables.For example, the sensor cables 140A of the prior art assembly 100interfere with sensor signals by inducing a phase shift on voltagereadings provided to controller 135. In addition, the time taken for avoltage reading sensed by the voltage sensors 130 to reach controller isnot insignificantly small. Accordingly, the controller 135 of the priorart assembly 100 does not receive highly accurate phase voltagemeasurements from the voltage sensors 130. In contrast, since thevoltage sensors 225A-225C are embedded within the capacitor switchhousings and/or the bushings 220A-220C proximate controller 230, shortsensor cables that do not significantly influence the accuracy ofvoltage measurements can be used to provide the voltage measurementsfrom voltage sensors 225A-225C to the controller 230. Therefore, voltagesignals provided by voltage sensors 225A-225C to controller 230experience minimal interference along their respective transmissionpaths.

In some embodiments, the voltage sensors 225A-225C are implemented asresistor networks configured to sense the respective voltages of phaselines 415A-415C. In other embodiments, the voltage sensors 225A-225C areimplemented as another type of voltage sensor that can be integratedwithin the solid dielectric bushing 220A-220C and/or capacitor switchhousings.

FIG. 5 illustrates a block diagram of an example control system 500 ofthe integrated assembly 200 according to some embodiments. The controlsystem 500 includes the controller 230. The controller 230 iselectrically and/or communicatively connected to a variety of modules orcomponents of the integrated assembly 200. For example, the controller230 is connected to the capacitor switches 215A-215C, the voltagesensors 225A-225C, the communication module 235, one or more additionalsensors 505, a user-interface 510, and/or a power supply 515.

The communication module 235 is configured to provide communicationbetween the integrated assembly 200 and one or more external devices(for example, a smart phone, a tablet, a laptop, etc.). For example, thecommunication module 235 includes one or more wireless and/or wiredtransmitters, receivers, and/or transceivers used for communicating withexternal devices. In some embodiments, the communication module 235 isconfigured to communicate with external devices operated by a utilityservice provider and/or a service technician. In such an embodiment, theintegrated assembly 200 communicates with the one or more externaldevices through a network. The network may be, for example, a wide areanetwork (WAN) (e.g., the Internet, a TCP/IP based network, a cellularnetwork, such as, for example, a Global System for Mobile Communications[GSM] network, a General Packet Radio Services [GPRS] network, a CodeDivision Multiple Access [CDMA] network, an Evolution-Data Optimized[EV-DO] network, an Enhanced Data Rates for GSM Evolution [EDGE]network, a 3 GSM network, a 4GSM network, a Digital Enhanced CordlessTelecommunications [DECT] network, a Digital AMPS [IS-136/TDMA] network,or an Integrated Digital Enhanced Network [iDEN] network, etc.). Inother embodiments, the network may be, for example, a local area network(LAN), a neighborhood area network (NAN), a home area network (HAN), orpersonal area network (PAN) employing any of a variety of communicationsprotocols, such as Wi-Fi, Bluetooth, ZigBee, etc. In yet anotherembodiment, the network includes one or more of a wide area network(WAN), a local area network (LAN), a neighborhood area network (NAN), ahome area network (HAN), or personal area network (PAN). In someembodiments, the communication module 235 communicates with one or moreperipheral devices in a supervisory control and data acquisition (SCADA)management system.

In some embodiments, the controller 230 is configured to communicatewith one or more additional sensors 505. For example, in someembodiments, the one or more additional sensors include current sensors250A-250C which are used to measure the current flowing through phaselines 415A-415C. In some embodiments, the one or more additional sensors505 include voltage sensors used to measure the respective voltagesacross the capacitors 210A-210C. In some embodiments, the one or moreadditional sensors 505 include one or more temperature sensors, moisturesensors, vibration sensors, and/or other types of sensors used tomeasure other physical and/or electrical characteristics of theintegrated assembly 200.

The controller 230 is further configured to communicate with auser-interface 510 of the integrated assembly 200. The user-interface510 is configured to receive input from a service technician and/oroutput information to a service technician concerning the integratedassembly 200. In some embodiments, the user-interface 510 includes theswitch operating handles 305A-305C used by a service technician tomanually operate the capacitor switches 215A-215C. In some embodiments,the user-interface 510 includes a display (for example, a primarydisplay, a secondary display, etc.) and/or other output devices(light-emitting diodes (“LEDs”), speakers, etc.) for outputting a statusof the integrated assembly 200 to a technician.

In some embodiments, all of the components of the user-interface 510 aresupported by the frame 205. In some embodiments, one or more of thecomponents of the user-interface 510 are located in a cabinet that canbe easily accessed by a service technician (e.g., positioned near thebottom of the distribution pole 245). For example, FIGS. 6A and 6Billustrate example embodiments in which a cabinet 605 including one ormore components of the user-interface 510 is mounted to the bottom ofthe distribution pole 245. In the illustrated example of FIGS. 6A and6B, the controller 230 is connected, via one or more cables, to thecomponents of user-interface 510 included in the cabinet 605. Forexample, the one or more cables may be implemented as power overethernet (POE) cables. In some embodiments, the one or more componentsof the user-interface 510 included in the cabinet 605 are componentsthat provide a user with control of one or more components of theintegrated assembly 200. For example, the cabinet 605 includes one ormore input mechanisms (for example, buttons, switches, a touch-screendisplay, a keyboard, a mouse, and/or the like) for controllingcomponents included in the integrated assembly 200. The one or moreinput mechanisms included in the cabinet 605 are used by a servicetechnician to, for example, manually open and/or close the capacitorswitches 215A-215C. In some embodiments, the cabinet 605 also includesone or more output mechanisms (for example, a display, a speaker, atouch-screen display, and/or the like) for providing informationassociated with the integrated assembly 200 to a service technician.

In some embodiments, the communication module 235 is located in thecabinet 605. In such embodiments, the communication module 235 may beconnected to the controller 230 and/or other components of theintegrated assembly 200 via the one or more cables. Furthermore, in suchembodiments, the communication module 235 includes one or more radiocommunication modules positioned in the cabinet 605 that can be easilyaccessed, maintained, and/or swapped out by service technicians.Accordingly, in such embodiments, service technicians can simply accessthe cabinet 605 to perform maintenance on the communication module 235instead of having to perform maintenance on the communication module 235at an elevated position near the high voltages present at the integratedassembly 200.

Referring back to FIG. 5 , the control system 500 of integrated assembly200 may further include a power supply 515 that is electrically and/orcommunicatively coupled to the controller 230. The power supply 515 isconfigured to selectively provide power to the various components of theintegrated assembly 200. In some embodiments, the power supply 515 isconfigured to power components of the integrated assembly 200 with powerreceived from phase lines 415A-415C. In such embodiments, the powersupply 515 includes one or more AC-AC converters, AC-DC converters,and/or DC-DC converters configured to convert the AC power supplied byphase conductor phase lines 415A-415C to a desired voltage before it isprovided to the various components of the integrated assembly 200. Insome embodiments, the power supply 515 includes an internal powersource, such as a rechargeable battery or a solar panel, for poweringthe components of integrated assembly 200.

In some embodiments, the controller 230 includes a plurality ofelectrical and electronic components that provide power, operationalcontrol, and/or protection to the components and modules within thecontroller 230 and/or the integrated assembly 200. For example, thecontroller 230 includes, among other things, an electronic processor 520(for example, a microprocessor or another suitable programmable device)and a memory 525.

The memory 525 includes, for example, a program storage area and a datastorage area. The program storage area and the data storage area caninclude combinations of different types of memory, such as read-onlymemory (ROM) and random-access memory (RAM). Various non-transitorycomputer readable media, for example, magnetic, optical, physical, orelectronic memory may be used. The electronic processor 520 iscommunicatively coupled to the memory 525 and executes softwareinstructions that are stored in the memory 525, or stored in anothernon-transitory computer readable medium such as another memory or adisc. The software may include one or more applications, program data,filters, rules, one or more program modules, and other executableinstructions. In some embodiments, the memory 525 includes one or moremodules configured to perform various functions of controller 230. Forexample, memory 525 may include a voltage comparison program used foranalyzing voltages received from voltage sensors 225A-225C. Memory 525may additionally or alternatively include a switch control moduleconfigured to generate signals (e.g., close and/or open signals) toinstruct the capacitor switches 215A-215C to open or close.

During operation of the integrated assembly 200, the controller 230receives phase line voltage signals from the voltage sensors 225A-225C.The controller 230 is configured to determine the magnitude and phase ofthe phase line voltages based on the received voltage signals. Forexample, the controller 230 is configured to determine the magnitude andphase of the voltage of phase line 415A directly based on voltagesignals provided by the first voltage sensor 225A. Similarly, thecontroller 230 is configured to determine the magnitude and phase of thevoltage of phase line 415B directly based on voltage signals provided bythe second voltage sensor 225B. Likewise, the controller 230 isconfigured to determine the magnitude and phase of the voltage of phaseline 415C directly based on voltage signals provided by the thirdvoltage sensor 225C.

The controller 230 is further configured to determine whether to open orclose the capacitor switches 215A-215C based on the determined voltagesof phase lines 415A-415C. During operation, the capacitor switches215A-215C are normally open. However, the controller 230 is configuredto close one or more of the switches 215A-215C in response todetermining that the phase line voltages are unbalanced and/or not inphase with one another.

When the controller 230 determines to close one or more of the capacitorswitches 215A-215C, a respective capacitor switch 215 should be closedat a time when the corresponding phase line voltage is at a waveformzero (e.g., at a zero-crossing). For example, if the controller 230determines to close capacitor switch 215A, the controller 230 shouldclose the capacitor switch 215A when the AC voltage of phase line 415Ais at a waveform zero. If a capacitor switch 215 closes at a time whenthe corresponding phase line AC voltage across the switch is not at awaveform zero, disturbances may occur due to heavy inrush currents asthe capacitors are charged. The disturbances include, for example,voltage dips, transient voltages, harmonics, resonance peaks and/orother undesirable effects on the electrical system. Such disturbancesmay result in damage to and/or other problems associated with sensitivecustomer equipment.

With respect to the prior art assembly 100 of FIG. 1 , the controller135 is incapable of accurately performing synchronous zero-voltageclosing of the capacitor switches 115. As described above, phase voltagemeasurements taken by voltage sensors 130 experience phase shiftingand/or are otherwise modified by the inductance of long sensor cable140A, and thus, the controller 135 cannot accurately determine awaveform zero when closing a capacitor switch 115. To account for thisdeficiency in synchronous zero-voltage closing, switched capacitor bankassemblies of the prior art have employed add-on control devices thatare configured to execute complex algorithms for estimating a respectivephase of each line voltage based on a single phase voltage measurement.In such prior art assemblies, a complex calibration process is requiredduring installation of the assembly at the distribution pole, as many ofthe third-party components (e.g., voltage sensors, controllers, add-onsynchronous zero-voltage controllers, etc.) are separately manufactured.Therefore, a prior art assembly may not be reliably used immediatelyafter installation, as additional calibration and commission of thethird-party components is required before the assembly is capable ofaccurately controlling the capacitor switches. In some cases, otherassemblies of the prior art blindly time their operations based on asingle-phase voltage sensor and calibration information regarding theelectrical system to which the system is connected. In such cases, theseprior art assemblies frequently close capacitor switches when linevoltages are at or near a waveform peak, and thus, induce significanttransient voltages on the distribution network in which they areinstalled.

In contrast, the integrated assembly 200 of the present disclosure isoperable to perform accurate synchronous zero-voltage closing of thecapacitor switches 215A-215C directly based on phase line voltagemeasurements without the need for an add-on control device or onsitecalibration. That is, since the phase line voltage measurements receivedfrom voltage sensors 225A-225C experience little to no phase shiftcaused by the sensor cables connecting the controller 230 to the voltagesensors 225A-225C, the controller 230 is operable to accuratelydetermine a waveform zero directly from the received voltagemeasurements. Thus, the integrated assembly 200 may have no need for anadd-on control device that is configured to estimate respective voltagephases when closing capacitor switches. Rather, the controller 230 canindependently determine a waveform zero of each phase line voltage whenclosing a respective capacitor switch 215A-215C. As described above,since the integrated assembly 200 is capable of accurately performingsynchronous zero-voltage closing of the capacitor switches 215A-215C,closure of the capacitor switches 215A-215C may not induce disturbancessuch as, for example, voltage dips, transient voltages, harmonics,resonance peaks and/or other undesirable effects, on the distributionsystem. Furthermore, the individual components of the integratedassembly 200 can be calibrated at a manufacturing site and/or otherlocation prior to installation at the distribution pole since everycomponent is included within the single package. Therefore, uponinstallation of the integrated assembly 200 on a distribution pole, theintegrated assembly 200 is immediately ready for operation without theneed for onsite calibration.

For example, the controller 230 is configured to determine whether thevoltage of phase line 415A is at a waveform zero directly from thevoltage measurement received from voltage sensor 225A. Similarly, thecontroller 230 is configured to determine whether the voltage of phaseline 415B is at a waveform zero directly from the voltage measurementreceived from voltage sensor 225B and configured to determine whetherthe voltage of phase line 415C is at a waveform zero directly from thevoltage measurement received from voltage sensor 225C. Accordingly, thecontroller 230 is selectively closes one or more of the capacitorswitches 215A-215C when the corresponding phase line voltages are at awaveform zero (e.g., zero-crossing).

FIGS. 7A-7K illustrate an integrated switched capacitor bank assembly,or integrated assembly, 700 according to some embodiments. Theintegrated assembly 700 has a similar configuration to the integratedassembly 200 of FIGS. 2A and 2B and/or FIGS. 6A and 6B; however, theintegrated assembly 700 is configured to be pad, or floor, mountedrather than mounted on a distribution pole. For example, the integratedassembly 700 also includes capacitors 210A-210C, capacitor switches215A-215C, dielectric bushings 220A-220B, integrated voltage sensors225A-225B, a controller 230, a communication module 235, a powertransformer 240, and/or optional current sensors that are supported by asingle frame. However, as shown, the integrated assembly 700 furtherincludes a cabinet, or housing 705, that contains the components of theintegrated assembly 700 while the integrated assembly 700 is mounted ona pad. Accordingly, the integrated assembly 700 offers the benefits ofintegrated assembly 200 while being mounted on a pad or otherground-level surface instead of a distribution pole.

Thus, the disclosure provides, among other things, an integratedswitched capacitor bank. Various features and advantages of the variousembodiments disclosed herein are set forth in the following claims. Inthe foregoing specification, specific examples, features, and aspectshave been described. However, one of ordinary skill in the artappreciates that various modifications and changes can be made withoutdeparting from the scope of the invention as set forth in the claimsbelow. Accordingly, the specification and figures are to be regarded inan illustrative rather than a restrictive sense, and all suchmodifications are intended to be included within the scope of presentteachings.

The benefits, advantages, solutions to problems, and any element(s) thatmay cause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeatures or elements of any or all the claims. The invention is definedsolely by the appended claims including any amendments made during thependency of this application and all equivalents of those claims asissued.

Moreover in this document, relational terms such as first and second,top and bottom, and the like may be used solely to distinguish oneentity or action from another entity or action without necessarilyrequiring or implying any actual such relationship or order between suchentities or actions. The terms “comprises,“ “comprising,” “has,”“having,” “includes,” “including,” “contains,” “containing” or any othervariation thereof, are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises, has,includes, contains a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus. An element proceeded by“comprises ... a,” “has ... a,” “includes ... a,” or “contains ... a”does not, without more constraints, preclude the existence of additionalidentical elements in the process, method, article, or apparatus thatcomprises, has, includes, contains the element. The terms “a” and “an”are defined as one or more unless explicitly stated otherwise herein.The terms “substantially,” “essentially,” “approximately,” “about” orany other version thereof, are defined as being close to as understoodby one of ordinary skill in the art, and in one non-limiting embodimentthe term is defined to be within 10%, in another embodiment within 5%,in another embodiment within 1% and in another embodiment within 0.5%.The term “coupled” as used herein is defined as connected, although notnecessarily directly and not necessarily mechanically. A device orstructure that is “configured” in a certain way is configured in atleast that way, but may also be configured in ways that are not listed.

It will be appreciated that some embodiments may be comprised of one ormore generic or specialized processors (or “processing devices”) such asmicroprocessors, digital signal processors, customized processors andfield programmable gate arrays (FPGAs) and unique stored programinstructions (including both software and firmware) that control the oneor more processors to implement, in conjunction with certainnon-processor circuits, some, most, or all of the functions of themethod and/or apparatus described herein. Alternatively, some or allfunctions could be implemented by a state machine that has no storedprogram instructions, or in one or more application specific integratedcircuits (ASICs), in which each function or some combinations of certainof the functions are implemented as custom logic. Of course, acombination of the two approaches could be used.

Moreover, an embodiment can be implemented as a computer-readablestorage medium having computer readable code stored thereon forprogramming a computer (e.g., comprising a processor) to perform amethod as described and claimed herein. Examples of suchcomputer-readable storage mediums include, but are not limited to, ahard disk, a CD-ROM, an optical storage device, a magnetic storagedevice, a ROM (Read Only Memory), a PROM (Programmable Read OnlyMemory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM(Electrically Erasable Programmable Read Only Memory) and a Flashmemory. Further, it is expected that one of ordinary skill,notwithstanding possibly significant effort and many design choicesmotivated by, for example, available time, current technology, andeconomic considerations, when guided by the concepts and principlesdisclosed herein will be readily capable of generating such softwareinstructions and programs and ICs with minimal experimentation.

The Abstract of the Disclosure is provided to allow the reader toquickly ascertain the nature of the technical disclosure. It issubmitted with the understanding that it will not be used to interpretor limit the scope or meaning of the claims. In addition, in theforegoing Detailed Description, it can be seen that various features aregrouped together in various embodiments for the purpose of streamliningthe disclosure. This method of disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter lies in less than allfeatures of a single disclosed embodiment. Thus, the following claimsare hereby incorporated into the Detailed Description, with each claimstanding on its own as a separately claimed subject matter

What is claimed is:
 1. A switched capacitor bank assembly comprising: afirst capacitor; a first switch selectively connected between the firstcapacitor and a first phase line; a first voltage sensor integratedwithin a housing of the first switch and used to sense a voltage of thefirst phase line; a controller including an electronic processor, thecontroller operably coupled to the first voltage sensor and the firstswitch; and a frame arranged to physically support the first capacitor,the first switch, the first voltage sensor, and the controller.
 2. Theswitched capacitor bank assembly of claim 1, wherein the first switch isa vacuum interrupter and includes a housing that is formed of a soliddielectric material.
 3. The switched capacitor bank assembly of claim 2,wherein the first voltage sensor is embedded in the solid dielectricmaterial of the housing.
 4. The switched capacitor bank assembly ofclaim 1, wherein the first switch further includes a solid dielectricbushing that connects the first switch to the first phase line; andwherein the first voltage sensor is embedded within the solid dielectricbushing.
 5. The switched capacitor bank assembly of claim 1, wherein thecontroller is further configured to: determine when a voltage of thefirst phase line is at a zero-crossing based on a voltage signalreceived directly from the first voltage sensor; and close the firstswitch when a voltage of the first phase line is at a zero-crossing. 6.The switched capacitor bank assembly of claim 1, wherein the controlleris contained within a second housing supported by the frame; wherein thesecond housing shields the controller from electromagnetic interference.7. The switched capacitor bank assembly of claim 6, wherein the secondhousing is a tank that physically supports the first switch; and whereinthe tank includes a handle used for manually operating the first switch.8. The switched capacitor bank assembly of claim 1, further comprising acommunication module configured to wirelessly communicate with anexternal device.
 9. The switched capacitor bank assembly of claim 8,wherein the communication module is contained within a third housingthat is physically supported by the frame.
 10. The switched capacitorbank assembly of claim 9, wherein the third housing is separate from asecond housing that encapsulates the controller.
 11. The switchedcapacitor bank assembly of claim 1, wherein the frame further includesan arrester mounting portion.
 12. The switched capacitor bank assemblyof claim 1, further comprising: a second capacitor physically supportedby the frame; a second switch selectively connected between the secondcapacitor and a second phase line, the second switch being physicallysupported by the frame; and a second voltage sensor integrated within ahousing of the second switch and configured to sense a voltage of thesecond phase line; wherein the controller is further configured todetermine when the voltage of the second phase line is at azero-crossing based on a second voltage signal received directly fromthe second voltage sensor.
 13. The switched capacitor bank assembly ofclaim 12, further comprising: a third capacitor physically supported bythe frame; a third switch selectively connected between the thirdcapacitor and a third phase line, the third switch being physicallysupported by the frame; a third voltage sensor integrated within ahousing of the third switch and configured to sense a voltage of thethird phase line; and wherein the controller is further configured todetermine when the voltage of the third phase line is at a zero-crossingbased on a third voltage signal received directly from the third voltagesensor.
 14. The switched capacitor bank assembly of claim 1, wherein theframe is mounted to a distribution pole.
 15. The switched capacitor bankassembly of claim 1, wherein the frame is mounted to a pad.
 16. Theswitched capacitor bank assembly of claim 15, further comprising acabinet arranged to contain the first capacitor, the first switch, thefirst voltage sensor, the controller, and the frame.
 17. A multi-phasepower system, comprising: a plurality of phase lines including a firstphase line, a second phase line, and a third phase line; and a switchedcapacitor bank assembly including: a plurality of capacitors including afirst capacitor, a second capacitor, and a third capacitor, a pluralityof voltage sensors including a first voltage sensor for measuring avoltage of the first phase line, a second voltage sensor for measuring avoltage of the second phase line, and a third voltage sensor formeasuring a voltage of the third phase line, a plurality of switchesincluding a first switch connected between the first phase line and thefirst capacitor, a second switch connected between the second phase lineand the second capacitor, and a third switch connected between the thirdphase line and the third capacitor, a controller including an electronicprocessor and coupled to the plurality of voltage sensors and theplurality of switches, the controller configured to selectively connect,using the plurality of switches, the plurality of capacitors to therespective ones of the plurality of phase lines based on signalsreceived from the plurality of voltage sensors, and a frame arranged tophysically support the plurality of capacitors, the plurality of voltagesensors, the plurality of switches, and the controller.
 18. Themulti-phase power system of claim 17, further comprising a distributionpole; wherein the frame is mounted to the distribution pole.
 19. Themulti-phase power system of claim 17, wherein the first voltage sensoris integrated in a housing of the first switch, the second voltagesensor is integrated in a housing of the second switch, and the thirdvoltage sensor is integrated in a housing of the third switch.
 20. Themulti-phase power system of claim 17, wherein the controller iscontained within a controller housing that shields the controller fromelectromagnetic interference.